Manufacture of envelopes



p 1958 v. E. HEYWOOD MANUFACTURE OF ENVELOPES 2 Sheets-Sheet 1 FiledJuly 10, 1957 INVENTOR Win21? EMEYWOO D ATTORNEY v. E. HEYWOOD 2,851,934MANUFACTURE OF ENVELOPES 2 Sheets-Sheet 2 :Ywo'oo ATTORNEY m mm Sept.16, 1958 Filed July 10, 1957 mm kmm fmw .VN

United States Patent Office Patented Sept. 16, 1958 MANUFACTURE OFENVELOPES Vincent E. Heywood, Worcester, Mass., assignor to UnitedStates Envelope Company, Springfield, Mass, a corporation of MaineApplication July 10, 1957, Serial No. 670,981

8 Claims. (CI. 93-62) This application is a continuation-in-part of mycopending application Serial No. 375,091 for Manufacture of Envelopes,which was filed August 19, 1953, now abandoned.

The present invention, like that of my United States Patent No.2,772,611, dated December 4, 1956, for Envelope Making Method andMechanism, deals with methods and means by which to obtain very rapidproduction of envelopes, through the elimination, in their continuous orrotary machine manufacture, of a certain production bottleneck which hasheretofore always operated against any appreciable stepping up of such amachines rate of envelope production.

This production bottleneck of all previous rotary envelope-makingmachines results, as described in my aforesaid patent, from a sequenceof operations that requires the successive envelope blanks to receivetheir imprints of seam-sticking glue whilst advancing rapidly inindividualized or spaced-apart relation at the maximum speed of blanktravel attained in the machine. That is to say, in all previous rotarymachines, a definite limit or ceiling on blank speed (and thus on themachines rate of envelope production) is imposed by the effect ofcentrifugal force on the rotating segments or dies that areconventionally employed to imprint the seam-sticking glue, since suchsegments or dies must operate at perpiheral speeds that keep pace withthe maximum speed of blank travel through the machine. Thus it follows,with any appreciable stepping up of such a conventional rotary machinesrate of envelope production, that minute glue'particles thrown offcentrifugally from the speeded up rotary dies or segments, willinvariably accumulate on blank-contacting machine surfaces exposedbetween the advancing spaced-apart blanks, to quickly foul up themachines operation, and necessitate its stoppage.

In the method and apparatus of my aforesaid patent, notwithstanding theleeway for much faster envelope production afforded by the relativelylow peripheral speed of its rotary seam glue imprinting device, thelatters tendency to throw off glue centrifugally is still a productionlimiting factor, especially when envelopes of large size or being made.

Moreover, the advantageous overgumming of seal flaps, by the two-purposerotary glue imprinting device of said patent, can be achieved only whenthe blanks are of substantially rhombic or diamond shape, presentingseal flap edges of the same angularity as the seam forming edges oftheir side flaps.

On the other hand, in rotary machine envelope manufacture by the novelflap holding and blank gluing sequences and arrangements of the presentinvention, no corresponding limitations are imposed, either on themachines rate of envelope production, or on the size or shape of theblanks which are converted thereby into envelopes.

Other and further objects and advantages of the instant invention willbe made apparent by the following detailed description thereof taken inconnection with the accompanying drawings, in which:

Fig. 1 is a plan view illustrating one form of the envelope makingmethod and apparatus of my invention, but omitting, for the sake ofclearness, certain glue receptacles and glue transfer rolls.

Fig. 2 is a vertical sectional view on the line 22 of Fig. l and showingalso the elements omitted from Fig. 1.

Fig. 3 is a larger scale view of one of the envelopes produced by myinvention, from blanks such as shown at the right-hand end of Fig. 1. I

Figs. 4 and 5 are views, similar to Figs. 1 and 2 respectively, ofanother form of my invention, Fig. 5 being a section on the line 5-5 ofFig. 4.

Like reference characters refer to like parts in the different figures.

My invention achieves extremely high speed envelope manufacture fromflat blanks of any conventional shape, such as shown in Figs. 1 and 4 bythe blanks A, A, each providing beyond its usual rectangular bodyportion 1 the opposite triangular side flaps 2, 2, and the oppositedissimilar bottom and seal flaps 3 and 4 respectively. It iscontemplated that a succession of these or other appropriate blanks willbe rapidly fed one by one, either from a supply stack, or, in the caseof substantially rhombic shapes, from suitable cut-ofi devices operableon a traveling paper web. In any case, the successive blanks, such as A,A, by the action of suitable feed rolls or the like (not shown except at5, 5 Figs. 2 and 5) are advanced rapidly, in spaced relation, to theillustrated mechanism, each with its bottom or back flap 3 leading, andwith its inside surface uppermost; preferably each blank A, during itssaid advance, receives lines of scoring 2a and 3a at the bases of itsside and bottom flaps.

The initial operation here, the same as in my aforesaid patent, is tofold inwardly the side flaps 2, 2 of each of the advancing spaced blanksA. For this purpose the mechanism, in the path of the rapidly advancingspaced blanks, provides conventional plowshare folding devices 6, 6 (seeFigs. 1 and 4) having suitably arranged lower and upper feed rolls 7, 7which continue each blanks advance at the same high speed imparted bythe rolls 5, 5. The plowshare folders 6, 6 operate in the usual and wellknown manner to obtain, by each blanks movement therethrough, the inwardfolding on score lines 2a, 2a of its side flaps 2, 2 against its bodyportion 1 to give it the parallel side edge folds 8, 8, as shown by theblanks B and B, Figs. 1 and 4. In this partly folded condition, thesuccessive spaced blanks, moving parallel to their side edge folds 8, 8,have their advance in the same direction (arrow x) continued by suitablehigh speed forwarding rolls 9, 9, operating at substantially the sameperipheral speed as the preceding rolls 5, 5 and 7, 7.

In the form of my invention shown by Figs. 1 and 2, the successivespaced partly-folded blanks next encounter cooperating spaced sets ofhigh speed rolls and low speed rolls (here shown at 10, 19' and 12, 12respectively) which function as hereinafter described to collect saidblanks progressively, for seam glue applying purposes, in the keepshingled sloW speed blank assembly shown at Y in Fig. 1. Close or deepshingling of envelope blanks is not, per se, new-having long been used,both with unfolded and partly-folded blanks, in the well known coatingor spreading process of seal flap gumming, as exemplified by the patentsof Novick No. 1,121,125, Pflanze No. 1,385,468, Novick No. 1,943,985 andWinkler et al. No. 2,132,227

The purpose and effect of such prior art close shingling is to disposein adjacent relation, for continuous en masse gumming, the insidemarginal surfaces of the blanks trailing seal flaps. When this closeshingled blank as- 3 semblyffor continuous seal flap gumming, isestablished, the margins of the respective blanks leading back flaps, onthe opposite or under side of the assembly, will also be exposed insimilar adjacent relation. But such adjacency of the back flap marginalareas 'is of no avail, for flapgurnming purposes, because it is of theoutside surfa ces rather th an'of theinside surfaces,'of said back lilapmargins. However, in the instant blank assembly Y, as hereinafterdescribed, the adjacency is of the inside rnarginal surfacesof therespective blanksleading back or bottomfiaps 3, 3.

Forthe progressive" formation ofthe illustrated blank --assembly Y, eachpartly folded blank B emerging from high speedrolls 9, 9 hasits'advancecontinued by an adjacent highspeed blankforwarding means,here shown as consistingofa lower roll'10, and a cooperating pair ofupper narrow rolls or-discs 10', 10', the latter engaging witheach'blank along its opposite side edge folds 8, 8. Said narrow rolls10', 10' are appropriately relieved, asshownatll, Fig. 2, so as torelease each blank and discontinue its high speed advance, at theinstant that its leading bottom flap 3 encounters and is seized "in thebite of a pair of "slow speed blank forwarding rolls 12,-12. 'Thelatter,'as a unit, are made adjustable (seearrows Fig. 2) toward andaway from rolls 10, 10', to accommodate 'the'spacing to blanks of longeror shorter dimension,"measuredin the direction of blank travel -throughthe mechanism.

Rolls 12, 12 have a peripheral speed which is only a very-small fractionof the peripheral speed of the preceding rolls5, 5, 7, 7, 9, 9 and 10,10'. Thus each partly folded blank'B, as it encounters the rolls 12, 12,has its speed of advance so drastically reduced that it isalmost'entirelyovertaken by the next following fast moving blank, beforethe 'latter, in turn, is slowed down by 'said'r'olls 12 12. In otherwords, while such a following fast-moving blank isbeing' advanced byrolls 9, 9 and 10, 10 from position B to position B (see Fig. 1) thepreceding blank, under the influence of the slow rolls 12, 12,will havemoved forward only the short distance represented on Fig. l by theshingle dimension S.

The latter is the width of the narrow marginal inside surface area ofeach blanks leading bottom flap 3 which 'not overtaken by the nextfollowing blank, in the above described successive overtakingoperations. Each such overtaking occurs in the absence of edgewisecollision' between the respective slow moving and fast moving blanks,and always with the latter projected for- "wa'rd'in overlying' ortopside relation to the former, by reason of high' speed rolls 10, 10',being arranged to operate,jas'shown'in Fig. 2, at a slightly lower levelthan the preceding high speed rolls 9, 9.

-Thus by conjoint action'of rolls 9, 9, 10, 10' and 12, 12, thesuccessive partly folded blanks B, B are progressively collected in aslow moving closely shingled or stepped assembly, as indicated at Y inFig. l. Therein each blank, except for an exposed narrow area ofwidth S-along "the inside margin of its leading bottom flap 3, is overlain andcovered by the next following blank.

Beyond the "range of forward adjustment of the shingling rolls -12, 12,are provided suitable roller elements which continue the slow speedadvance of the -shingled=blank assembly Y, and which serve also tospread or roll seam sticking glue onto the exposed narrow bottom'fiapmargins of its constituent partly folded blanks. These rollerelementscomprise a lower roll 13 and a cooperating upper roll which, for seamgluing of blanks such 'as'A, A with non-meeting side flaps, is made intwo spaced sections 14, 14, mounted on a common shaft 15. The rollerelements 13, 14 have the same low peripheral spe'ed as the shinglingrolls'12, 12, so as to 'continue the lattersslow speed advance of theclosely shingled blank assembly Y.

' The peripheral surfaces of the 'two'upper roll sectionsspeed-forwarding means forpreserving and maintaining marginallyglued'bottom flap 3', on its score line 3a. folding operation, forwhicheach blank is conditioned Q4 14, 14 are continuously supplied withseam sticking glue by a conventional glue transfer roll 16, associatedwith a glue supply tub 17, as'shown in Fig. 2. 'This glue, by the slowrotation of the spaced roll sections 14, 14, is continuously andprogressively spread onto the adjacently exposed inner surfaces ofleading bottom flap margins of slow moving blank-'= assembly Y in twoparallel stripes,- as indicated by-the stipling 18, 18 in Fig. 1. Anytendency of said bottom flap margins to be deflected upwardly,asbyadhesion 'to the-glue spreading rolls able high speed blankde-shinglingmeans are shown at 22, 22', in spacedrelation to'the slowspeed rolls 13, 14. In the intervening space I provide suitable slow theclosely shingled blank assembly Y and for continuing I its-advance atthe same -slow=speed imparted thereto by the rolls 12, 12 and 13, 14.This intermediate slow 'speed forwarding means consists, as here shown,of'a lower roll 21 and a pair of -aligned cooperating narrow rolls ordiscs '21', 21', "the latter'engaging the shingled blanks along theiroverlapped sideedge folds 8, 8, be-

yond the outeredges of the rolled on'seam gluing 18. Said slow speedrolls 21, 21 are arranged for adjustment as a unit (see-arrows; Fig-2),-toward or away from the high speed de-shingling elements 22, 22',inthe'same manner and'for the same purpose asthe" corresponding adjustmentabove described of the shingling rolls 12, 12, toward or away :from thehigh speed blank forwarding rolls 10, 10'.

Theinitial elements of my' afOresaid hi'gh spe'ed deshingling meanscomprisefas'here shown,- a lower roll 22 and a cooperating pair ofnarrow upper rolls or discs 22', the latter enga'gihg each" arrivingblank by-- its side edge folds 8, 8, beyond the'outer ends ofits'r'narginal bottom flap gumming. 'Said' narrow' rolls22'- areappropriately relieved, as shown at 23, Fig." 2, to obtainintermittently the one' by one seizure andspeed up of successive frontblanks of assembly Y,- as each, by said assemblys slow t'ravel,"is-moved' i'n'to' -seizu're position, in the interval during 'which'the" reliefs 23- a're opposite the-roll 22. Each seized blanks speedupis-very drastic,

since rolls 22, 22, operate at-the same-high peripheral "speed'as thepreceding"blank' forwarding rolls 5, 5,7, 7,

9, 9, and '10, "HQ-thereby in this progressive de-shingling of theblanks to 'reSto're to each in t'u'rnits original high speed of advanceand its' s'p'ac'ed relation to the" blank next following.

This same high peripheral speed is also imparted to immediatelyadjacent'rollerelements, consisting as here shown of a lower drum or cylinder'24and a'pairof cooperating-narrow rolls or 'discs 24' for seizing andforwarding each speeded upblank' by its side edge folds 3, 8, before thelatter are released by'the'reliefs 23' of the preceding narrow high"s'p'e'ed"rolls 22. Said"elements 24, 24' besides"participating, asabove/described,

in these successive high speed dc-shingling operations, at

the leading end of blank assembly Y, are also involved in the ensuingfolding over of each de-shingled' blanks This by being individualizedthrough its high speed pull out from the shingled asserhbly'Yfmay'beper'formed, as here'shown, by an" arrangement "similar in" characterto that disclosed for bottom flap folding in my aforesaid Patent No.2,772,611.

That is to say, the drum cylinder 24 is shown in Fig. 2 as mounted, forits high speed rotation, on a stationary hollow shaft 25, whose interioris connected to any suitable source of suction, such as a vacuum pump,not shown. Stationary hollow shaft 25 has a longitudinal port 26, ofsubstantially 90 circumferential extent, with which is adapted toregister periodically the inner end of a passage 27 extending radiallythrough the cylinder 24, and terminating on its periphery in anelongated slit or slits, for the suction seizure, on each revolution ofsaid cylinder, of a so-individualized fast moving blank.

The high speed counterclockwise rotation of cylinder 24 is so timed tothe high speed blank travel, that each blank is suction seized at orjust behind its score line 3a, by the terminal slit or slits of passage27, as the latter, substantially at the top of its travel, comes intocommunication with the port 26 of shaft 25. The blank 18 is shown inFigs. 1 and 2 as having been thus suctionally seized and drawndownwardly, by the cylinders rotation, toward the line of bite betweensaid cylinder 24 and an adjacent pressing and forwarding cylinder 28,which rotates clockwise at the same high peripheral speed as that ofcylinder 24.

Cylinder 28 is mounted, for its high speed rotation on a stationaryhollow shaft 29, also connected to said source of suction, and providinga longitudinal port 30, of substantially 90 circumferential extent, withwhich is adapted to register the inner end of a radial passage 31 ofcylinder 28. Said passage 31 terminates on said cylinders periphery inan elongated slit or slits for the suction seizure, on each revolutionof said cylinder, of each individualized blank which, as abovedescribed, is drawn downwardly by the cylinder 24.

The respective ports 26 and 30 of hollow shafts 25 and 29 are sopositioned, as shown in Fig. 2, that suction through passage 31 becomesavailable, for blank seizure by cylinder 23, substantially coincidentalwith the cut-off of suction through passage 27, to release such blankfrom the cylinder 24. The transfer of each blank, from cylinder 24 tocylinder 28 occurs as their respective suction passages 27 and 31 comeinto opposing substantial alignment, with the passage 31 seizing theblank in the same location as passage 27, viz. at or just behind itsscore line 311. As each blank moves downwardly (see B with cylinder 24,its forwardly projecting glued bottom flap 3, ahead of said score line,is deflected upwardly, away from, contact with the oppositely travelingsurface of cylinder 28, by engagement with a suitable stationary guardplate 32 (see Fig. 2). I

Such deflection tends to bend upwardly each bottom flap 3 on itssuctionally gripped score line 3a, said bending, in the case of blank BFig. 1, being reflected by a foreshortening of its bottom flap 3. Saidbending increases, and ultimately becomes a pronounced transverse fold(see 33, Figs. 1 and 3) as the downward high speed movement, first bycylinder 24 and then by cylinder 28, carries each blank, score lineleading, between said two cylinders. The latters pressing actionaccentuates said fold, and then is exerted on each individualized blank,to obtain effective overlapped adhesive seam connection forpocket-forming purposes, between its bottom flaps marginal wet gluing 34and the proximate edges of its previously infolded side flaps 2, 2.

With each individualized blank thus converted in sucsession by thefolding in of its bottom flap 3, to a pocketed element, movingdownwardly, fold 33 leading 'on cylinder 28, its release from saidcylinders suction passage 31 takes place on latters at the bottom of itstravel, beyond the port This transfers the advance of each pocketedelement (a complete envelope except t'or seal flap gluing) to the bitebetween cylinder 28 and a cooperating lower roll which rotatescounterclockwise at the same high peripheral speed as said cylinder. Itwill be understood that successive pocketed elements arriving one afteranother between cylinder 28 and roll 35 are projected forward in spacedrelation at the same high speed of movement as the successive flatblanks A. A are fed to the mechanism by the rolls 5, 5, 7,7 and 9,9.

My invention contemplates applying of glue to the trailing seal flaps 4,4 of these pocketed elements (complete envelopes with unglued sealflaps) by the prior art spreading or coating process, substantially inthe manner disclosed in the aforesaid Novick Patent No, 1,121,125. Forthe required close shingling, to bring into adjacency the insidemarginal areas of the respective trailing seal flaps 4, 4, each pocketedelement emerging from rolls 2%, 35 has its advance continued by adjacenthigh speed forwarding means, here shown as consisting of a lower roll 36and a cooperating pair of upper narrow rolls or discs 36, 36' forengaging each element along its opposite side edge folds 3, S. Saidnarrow rolls 36', 36 are appropriately relieved, as shown at 37, Fig. 2,so as to release each pocketed element, and discontinue it high speedadvance, substantially at the instant that its side edge folds 8, 8encounter and are seized by low speed shingling devices, here shown asconsisting of a lower roll 4% and a cooperating pair of upper narrowrolls or discs 49', 49, for engaging the successive pocketed elements bytheir side edge folds 8, 8. Slow speed rolls 4%, 46' as a unit are madeadjustable toward and away (see arrows, Fig. 2) from the high speedrolls 36, 36', to accommodate the spacing to pocketed elements of longeror shorter dimension, measured in the direction of their travel throughthe mechanism.

Rolls 40, 49' have a peripheral speed which is only a very smallfraction of the peripheral speed of the preceding rolls 36, 36. Thuseach pocketed element, as it encounters the rolls 4%, 40' has its speedof advance so drastically reduced that it is almost entirely overtakenby the next following fast moving pocketed element, before the latter inturn is slowed down by the rolls 40, 4%). in this overtaking orshingling action, provision is made for each fast moving pocketedelement to be projected beneath the preceding slowed down pocketedelement, by disposing the bight of slow rolls 40, 46 at a slightlyhigher level than the bight of fast rolls 35, 36' (see Fig. 2), andproviding an upwardly sloping guide or skid 39 between said roll pairsto direct the bottom edge folds $3 of successive pocketed elementsbetween the rolls 46, Additionally, for the same purpose, the lower highspeed roll 35 is formed centrally with a raised projection 32 which,following release of each pocketed element by the reliefs 37, is adaptedto elevate said elements trailing seal flap 4, so that the leadingbottom edge fold 33 of the next following fast moving pocketed elementwill always be projected, by rolls 28, 3S, beneath said trailing sealflap.

Thus by conjoint action of rolls 28, 35, 35, 35' and 40, 44), thesuccessive spaced apart pocketed elements are progressively collected ina slow moving closely shingled or stepped assembly, as indicated at Z inFig. 1. Therein each pocketed element overlies and covers the nextfollowing pocketed element except for an exposed narrow area, of shingledimension t, along the inside margin of the latters trailing seal flap4, Beyond the range of forward adjustment of rolls 4%, 40' I providesuitable means for rolling or spreading glue, for envelope sealingpurposes, upon the adjacent exposed trailing seal flap margins of thepocketed elements of the slow moving shingled assembly Z. Such means, asshown, consists of a lower roll 41 and an upper roll 42, both operatingat the same low peripheral speed as the shingling rolls 40, 40' tocontinue the latters slow speed advance of the shingled assembly Z.

The periphery of upper roll 42 is continuously supplied with seal flapglue by a conventional glue transfer roll 43, associated with a gluesupply tub 44, as shown in -Fige 2. This glue bytheslowirotationiofiroll 42 is continuously-sand progressively spread onto1 the exposed trailing sealflap 'marg'insof the slowmoving assembly Z,in a wide band 'or stripe, as indicated by the' stippling 45 -in Fig.1.Thus eachpocketed element of said assembly 46 and-cooperating uppernarrow rolls or discs 46,'46',

the latter contacting the:shingled assemblyZ beyond its gluing'45. Saidrolls-"46, 46rhave the same low peripheral-speed astheshingling rolls40,-, thereby to maintainintact the shingled assemblyZ and to deliversame progressively at. slow speed 'to' a suitably elongated dryingconveyor. The latters-receiving' end is here indicate by conventionallowerrand-upper pairs of pulleys 47, 47, which, in conjunction .withother pulleys, not shown, carry the usual-narrow lower and upper pairsof elongated endless traveling belts-48, '48, adapted to contactopposite surfaces of the overlapped envelopes along their side edges,beyondwthe wet gluing on their seal flaps, to convey them, in shingledassembly, through a drying tunnel or the like, not shown.

In the form of my invention shown by Figs. 4 and 5,

the successive spacedapart partlysfoldedblanks B, B,

beyond the high speed forwarding rolls 9, 9, undergo as before a topsideshingling operation in which each blank is partially overtaken andoverlapped by the one next following. But this topside shingling is hereused to collect the blanks for seam gumming, not in a close orderassembly such as shown at Y in Fig. l, but rather in the shallowlyshingled assembly shown in Fig. 4 at F, which assembly F,'except for itsbeing produced 'by topside overtaking of each blank, is similar to theshallowly shingled blank assembly shown at .E in Fig, l .of my aforesiadPatent No. 2,772,611.

For the progressive formation of theillustrated blank assemblyF,eachpartly folded blank B emerging from high speed rolls 9,-'9 -has itsadvance continue d by adjacent high speed forwarding means, here shownas consisting of a lower roll and a cooperating pair of uppernarrow'rolls or discs 50', 50', the latter engaging with each blankalong its opposite side edge folds 8, 8. Said narrow rolls 50, 50' areappropriately relieved, as shown :at' 5-1,"Fig. 5, so as'to release eachblank and discontinue its high speed a'dvance, at the instant that itsleading back or bottom flap 3 encounters and'is seized in the bite of apair ofslower speed-blank forwarding rolls 52, 52. The latter, as aunit, are made adjustable (see arrows Fig. 5) 'tow'ard' and away fromthe rolls 50, 50, to acc'ommodate the spacing to blanks of longer orshorter dimension, measured in the direction of blank travel.

each partly folded blank B, as it encounters the rolls '52, 52, has itsspeed of advance'so reduced that it is overtaken for about one-halfofits length by the next following fast moving blank B, before the latter,in turn, is slowed down by said rolls 52, 52. In other words,

while' 'such afollowing fast moving blank is being advanced by rolls 9,9 and 50, 50' from position B to position B (see Fig. 4) the precedingblank, under the influence of the slower rolls 52, 52 will have movedforward slightly less than one-half as far, i. e., to a position BFig.4, wherein its trailing'seal'flap 4 and parts of 1 its infolded sideflaps 2, 2 are overlain by'the forward portion of the following blank B.V

' Thus it is "by"thesesuccessive overtakings that the partly foldedblanksare collected progressively in the illu'strated shallowly shingledassembly P, which advances" To obtain. constant advance of blankassembly F, atlthe same reducedspeed imparted byxshingling rolls 52, 52,the-mechanism has three sets .of suitablyspaced lowspeed forwardingrolls, whichzhave. engagement. or. bite with the assemblys successiveblanks alongtthe.lattersiside edge folds 8, 8. Eachrof these setsoflowspeed rolls consists of a lower roll53 and arpair ofalined'cooperating upper narrow rolls or discs 53', 53', all havingthe samelow. peripheral speed as the shingling'rolls 52, 52, so as to keep theassembly F intact during the imprinting of seaming gluealong thesuccessive blanks leading back flap margins, which .marginsin saidassembly are spaced apartby the reducedrdistance d, Fig. 4.

The seam glue imprinting means is here shown as interposed between thefirst. and second sets of low speed forwarding rolls 53, 53.Saidimprinting means comprises a lower or. platen roll 54, and an uppershaft 55 of smaller .diameter than said platen roll 54. Said shaft 55 isformed with a pair ofspaced narrow raised helical ribs 56,. 56 ofopposite inclination, such that eachribs'outer surface, by the rotationof shaft 55, moves in a circumferential path whoselength is .the reduceddistance d (Fig.4) that separates the successive. leading back flapmargins of the overlapped blanks of assembly F. Outwardly of the helicalribs 56, 56, the shaft 55 is formed with narrow collars orflanges 57,57. for cooperation with the platen roll 54, to maintain the slow speedadvance of assembly F, by engagement with itsconstituent blanks alongtheir side edge folds 8, 8.

At each rotation of shaft 55, the outer surfaces of its helical ribs 56,56 receive wet glue from their contact with a rotating overhead glueroller 58 (Fig. 5) which is 'vergent seam glue imprints as shown at 60,60, Fig. 4.

Beyond the final (left-hand) set of slow speed forwarding rolls 53, 53,each foremost blank; of assembly F, is, in its turn, seized, speeded up,and'pnlled away from said assembly by the same high speed de-shinglingmeans 22, 22' as are employed in Figs. land 2 for. de-shingling thesuccessive foremost blanks ofthe blank assembly Y in saidfirst-described form of my invention. Beyond said high speedde-shingling means 22, 22' of Figs. 4 and 5, the successive blanks arehandled and converted into envelopes in exactly the same fashion, and byexactly the same means, as described above for Figs. 1 and 2, Since saidhandling and converting means in Figs. 4 and 5 are designated by thesame reference characters as are.v used in Figs. l and 2, it is notnecessary here to describethe same in further detail.

Any suitable gearing, not here shown, may be employed to impart to theseveral rolls their respective high peripheral speeds, and lowperipheral speeds, as herein specified. Also, the illustrated mechanism,in addition to its adjustments above described for various lengths ofblanks, can readily be accommodated to the handling of different widthsof blanks, merely 'by adjusting, toward or away from center line 22 ofFig. 1 (or center line 5--5 of Fig. 4), the positions of the severalsets of narrow forwarding rolls 10, 21, 22, 24', 36', 40, 46, 50 and 53on their respective shafts.

Under all conditions, and regardless of the shape or size of the blanksbeing handled, my invention makes possible the rotary machinemznufacture of envelopes at much higher rates of production than everachieved heretofore. This results from my herein described sequence ofenvelope making operations which obtains all blank gluing, both for sealflap and seam sticking purposes, without any limiting effect whatsoeveron the speed of blank movement to and through the machine.

Actually, the envelope production rate, in the preferred form of myinvention shown in Figs. 1 and 2, is limited only by the speed at whichit is practicable and feasible to perform on the blanks in process thetwo described flap folding operations, viz., for each blank, the initialinfolding of its side flaps, and the subsequent folding over of itsmarginally glued back or bottom flap into adhesive seam connection withits side flaps. in other Words, the rate of envelope production suffersno limitation or curtailment whatsoever, from the operations of applyingto successive blanks (l) the seam sticking glue and/ or (2) the sealflap glue. This is because of the fact that the gluing is applied,progressively and en masse, to inside seam flap margins as well as toinside seal flap margins of the successive blanks, with the lattercollected, for each glue applying operation, in a slow speed closelyshingled or stepped assembly that exposes only the desiredglue-receiving inside flap margins to the action of the gluing roller orwiper.

I claim:

1. In the manufacture of envelopes from a succession of flat blanksadvancing at high speed in spaced relation with their bottom flapsleading, the improvement which consists in folding inwardly the sideflaps of the successive so-advancing spaced blanks, so progressivelycollecting the successive so-folded blanks in a low speed closelyshingled assembly as to expose in adjacent relation, for continuous enmasse gluing, the inside surfaces of the respective blanks leadingbottom flap margins, progressively spreading glue, by the low speedadvance of said assembly, upon the so-exposed adjacent inside marginalsurfaces of said leading bottom flaps, speeding up in succession eachsoglued blank to restore its initial high speed of advance and itsspaced relation to the blank next following, folding inwardly the bottomflaps of the successive speeded-up blanks, to produce, by adhesion ofsaid bottom flaps to the previously infolded side flaps, a succession ofpocketed elements, so progressively collecting the successive pocketedelements in a low speed closely shingled second assembly as to expose inadjacent relation, for continuous en masse gluing, the inside surfacesof the respective elements trailing seal flap margins, and progressivelyspreading adhesive by the slow speed advance of said second assembly,upon the adjacent so-exposed trailing seal flap margins of theso-shingled pocketed elements.

2. In the manufacture of envelopes from a succession of flat blanksadvancing at high speed in spaced relation with their bottom flapsleading, the improvement which consists in folding inwardly the sideflaps of the suc- .cessive so-advancing spaced blanks, so progressivelycollecting the successive so-folded blanks in a low speed closelyshingled assembly as to expose in adjacent relation, for continuous enmasse gluing, the inside surfaces of the respective blanks leadingbottom flap margins, progressively spreading glue, by the low speedadvance of said assembly, upon the so-exposed adjacent inside marginalsurfaces of said leading bottom flaps, speeding up in succession eachso-glued blank to restore its initial high speed of advance and itsspaced relation to the blank next following, folding inwardly the bottomflaps of the successive speeded-up blanks, to produce, by adhesion ofsaid bottom flaps to the previously infolded side flaps, a succession ofpocketed elements, so progressively collecting the successive pocketedelements in a low speed closely shingled second assembly as to expose inadjacent relation, for continuous en masse gluing, the inside surfacesof the 10 respective elements trailing seal flap margins, progressivelyspreading adhesive by the slow speed advance of said second assembly,upon the adjacent so-exposed trailing seal flap margins of theso-shingled pocketed elements, and continuing the slow speed advance ofsaid second assembly for the drying of the adhesive on said seal flaps.

3. In envelope making mechanism, means for advancing fiat blanks at highspeed in spaced relation, with their bottom flaps leading, meansoperative on each so-advancing blank to fold inwardly its side flaps,means for so pr0 gressively coilecting the successive so-folded blanksin a low speed closely-shingled assembly as to expose in adjacentrelation, for continuous en masse gluing, the inside surfaces of therespective blanks leading bottom flap margins, means for progressivelyspreading glue, by the slow speed advance of said assembly, upon theso-exposed adjacent inside bottom flap margins of the successiveshingled blanks, means for restoring in succession to each so-gluedblank its high speed advance and its spaced relation to the blank nextfollowing, means for folding inwardly in succession the bottom flaps ofthe speeded-up blanks to produce, by adhesion of said bottom flaps tothe previously infolded side flaps, a succession of pocketed elements,means for so progressively collecting the successive pocketed elementsin a low speed closely-shingled second assembly as to expose in adjacentrelation, for continuous en masse gluing, the inside surfaces of therespective elements trailing seal flap margins, and means forprogressively spreading glue, by the slow speed advance of said secondassembly, upon the adjacent so-exposed trailing seal flap margins of theso-shingled pocketed elements.

4. In envelope making mechanism, means for advancing flat blanks at highspeed in spaced relation, with their bottom flaps leading, meansoperative on each so-advancing blank to fold inwardly its side flaps,means for so progressively collecting the successive so-folded blanks ina low speed closely-shingled assembly that each blank, ex-

cept for the margin of its leading bottom flap is overlain by thenext-following blank, means for progressively spreading glue, by theslow speed advance of said assernbly, upon the so-exposed adjacentbottom flap margins of the successive shingled blanks, means forrestoring in succession to each so-glued blank its high speed advanceand its spaced relation to the blank next following, means for foldinginwardly in succession the bottom flaps of the speeded-up blanks toproduce, by adhesion of said bottom flaps to the previously infoldedside flaps, a succession of pocketed elements, means for soprogressively collecting the successive pocketed elements in a low speedcloselyshingled second assembly that each element, except for the marginof the trailing seal flap of its blank, underlies the preceding element,means for progressively spreading adhesive, by the slow speed advance ofsaid second assembly, upon the adjacent so-exposed trailing seal flapmargins of the so-shingled pocketed elements, and means for continuingthe slow speed advance of said second assembly for the drying of theadhesive on said seal flaps.

5. In the method of making envelopes from a succession of flat blanksadvancing in spaced relation with their bottom flaps leading, theimprovement which comprises folding inwardly the side flaps of thesuccessive so-advancing spaced blanks, successively retarding theadvancing so-folded blanks such that each blank is superimposed upon thepreceding blank to the extent that only the leading marginal edges ofthe bottom flaps are uncovered, spreading glue on the so-exposed leadingmarginal edges of said bottom flaps, successively accelerating theadvancing so-folded and so-glued blanks so as to provide another spacedrelationship between successive blanks, folding inwardly the bottom flapof each blank in succession so as to form a succession of pocketedelements, successively retarding the advancing pocketed elements suchthat each element, except for the exposed marginal edge of its trailingseal flap, underlies the preceding element,

,and, spreadi g ,gl.ue upon the so-exposed trailing seal flap :margins.

;6. lnlan-envelopemaking machine, means'for-iadvanc- .ing .flat envelopeblanks in spaced relation with; their bottom, flaps leading, meansforfolding inwardly the side flaps of each advancingblank, means forsuccessively retarding 'theso-folded blanks such that each blank issuperimposed upon the next preceding blank to the; extent that only themarginal edges of the leading bottom flaps vare exposed, means forwiping glue on the so-exposed ."marginal edges of said bottom flaps,means for succes- -sive1y accelerating the so-glued blanks, means forfolding inwardly ingsuccession the bottom flaps of said blanks so-as:to; produce a succession of pocketed elements,--means for; retardingin succession the advancing pocketedelements-such-that:each-element,-except for the exposed .marginal-edgeofitsv trailing seal flap, underlies the prercedingielement, and means forwipingglue upon the exposed marginal; edges, of; said :trailing sealflaps.

7. In 'the'manufacture of envelopes from a succession oftflat blanksadvancing athigh speed inspaced relation withtheir back or bottom flapsleading, the, improvement which consists of folding inwardly the, sideflaps of the successive so-advancing spaced blanks, reducing at the samepoint in .each partly foldedblanks movement its speed of advance, .suchthat each blank is superimposed upon the preceding blank, in aprogressivelyformed shingled blank assembly moving at said reducedspeed, applying glue, during the slow speed advance of said blankassembly, to the respective inside leading marginal surfaces of thesuccessive back or bottom flaps of said assemblys constituent blanks,speeding up in succession each so-glued blank to restore its initialhigh speed of advance and its spaced relation to the blank next follow-"ing,folding inwardly the bottom flaps of the successive speeded-upblanks, to produce, by adhesion of said bottom' flaps to the previouslyinfolded side flaps, a succesing fiat blanks at high speed in spacedrelation with their back or bottomfiaps leading, means operative on eachso-advancing blank to fold inwardly its side flaps, means for reducingat the same point in each so-folded blanks movement its speed ofadvancement, such that each blank is superimposed upon the precedingblank in a p rogressively formed shingled blank assembly moving at saidreduced speed, means for applying glue, during the slow speed advance ofsaid blank assembly to the respective inside leading marginal surfacesof the successive back or bottom flaps of said assemblys constituentblanks, means for restoring in succession to each so-glued blank itshigh speed advance and its spaced relation to the blank next following,means for folding inwardly in succession the bottom flaps of thespeeded-up blanks to produce, byadhesion of said bottom flaps to thepreviously infolded side flaps, a succession of pocketed elements, meansfor so progressively collecting the successive pocketed elements in alow speed closely-shingled second-assembly as to expose in adjacentrelation, for continuous en masse gluing, the inside surfaces of therespective elementstrailing seal flap margins, and means forprogressively spreading glue, by the slow speed advance of said secondassembly, upon the adjacent so-exposed trailing; seal flap margins oftheso-shingled pocketed elements.

No references cited.

